Need a bit of help settings up Taskpad...

One of our Clients has a couple of people using Taskpad to access AD on their server to reset passwords etc when needed.

One of them got a new computer and is unable to access it now. I'm trying to set it up, but can't get AD to show on MMC on his new computer.

Any ideas on what I need to do? Google hasn't helped.

Server 2012 R2 and Windows 10 Pro 1903.